Broccoli Type Adapted for Ease of Harvest

ABSTRACT

A broccoli plant characterized in having an exerted head having a crown higher than the leaf canopy and a harvestable head of at least about 200 grams when planted at a density of 40,000 plants per hectare, where the harvestable head comprises the top 25 centimeters of said stalk.

CROSS REFERENCE TO RELATED APPLICATION

This application is a continuation of U.S. application Ser. No.12/656,445, filed Jan. 29, 2010 (pending), which is a continuation ofU.S. application Ser. No. 10/850,077, filed May 19, 2004 (now U.S. Pat.No. 8,030,549), which applications are incorporated herein by referencein their entireties.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to the field of plant breeding and varietydevelopment, and more specifically, relates to the development of a newand distinct broccoli type for easier harvest.

2. Description of Related Art

Broccoli is a native of the Mediterranean region, and has been grown inItaly from at least the time of the Roman Empire. It was a favoritevegetable in Rome where a variety called Calabrese was developed. Beforethe Calabrese variety was cultivated, Romans ate a purple sproutingbroccoli that turned green when cooked.

During the 16th century, the popularity of broccoli spread throughoutEurope and it was cultivated in the United States by the late 18thcentury. However, broccoli did not become a commercially important cropin the United States until after World War II. In the late 20th centurybroccoli became popular in the United States, and has recently beentouted for its health benefits. Presently, the United States is theworld's largest producer of broccoli, with most of the broccoli grown inthe U.S. marketed as fresh produce. The leading broccoli-producingstates are California (with approximately 90 percent of the crop),Arizona, Texas, and Oregon. Broccoli also is grown on a large scale inSpain, northern Europe, Central America and Australia.

Broccoli is a member of the Cruciferae family, as are cabbage,cauliflower, brussels sprouts, kohlrabi, turnips, mustards, and Chinesecabbage. The word broccoli comes from the Italian word “brocco”, whichmeans arm branch, more particularly, from the word broccolo, which isthe diminutive form of brocco and refers to cabbage sprout. Broccoli isplural and refers to the numerous shoots in this form of Brassicaoleracea.

There are several types of broccoli, the most popular being thesprouting/Italian broccoli that includes the Calabrese-type, Brassicaoleracea L convar. bonytis (L.) Alef. var. cymosa Duch. (the nameadopted by the Community Plant Variety Office (CPVO)). Heading broccolihas several attributes more commonly attributed to cauliflower (anexample being the Romanesco type, which is increasing in popularity).The true Calabrese type is a primitive type with many secondary heads(origination from the axils of the leaves). The heads are also splitinto smaller parts, that do not form a solid head.

Another broccoli, “broccoli rabe”, or, “broccoli raab” has loose greensprouting heads (more like loose broccoli than cauliflower) that areharvested and eaten as greens along with surrounding leaves.

Morphologically, cauliflower and heading broccoli are similar. Thebroccoli plant, however, generally produces a green head with a longerand more slender floret-stalk than cauliflower. When the main terminalhead of a broccoli plant is harvested, the axillary buds lower on themain stem are induced to develop into smaller heads, which can also beharvested.

Much of the breeding of modern varieties has focused on heading types,which have been bred to produce a single, large head at the plant axis,reducing the number of secondary heads, though in some regions after theharvest of the main head secondary heads are still harvested, sometimesreferred to as “asparagus broccoli”.

The most commonly grown broccoli variety is Marathon, which showsaverage to good vigor, with the height of the head at about 40-50 cmabove the ground, and the height of the canopy at about 60-70 cm.Maturity is medium to late (70 days in the summer from planting), withsecondary heads present. The color of the head is grey/green, with thehead forming a medium dome in shape. The bead on the heads is fine, thestem diameter is medium, somewhat sensitive to hollow stem, and thevariety has intermediate resistance to downey mildew (Peronosporaparasitica). Marathon is best adapted to cool season cultivation, (fall,winter) and the plant density varieties between 40,000 to 80,000 plantsper ha.

Most broccoli varieties grow best on well-drained soils that hold water.In sandy soils, irrigation is important for optimum plant growth and tomaintain proper main head and side shoot development. Flower heads (theedible portion of sprouting broccoli) develop relative to ambienttemperatures, and in the heat of summer, broccoli heads maturing in Julymay produce flowers and seeds more quickly (four to six days) than thosematuring in the cooler spring and fall periods.

To be considered good quality, broccoli heads should be closed, darkgreen and tight (no yellow petals showing). A deep green, uniform headcolor is a desirable trait in broccoli. Broccoli heads “green” accordingto the amount of sunshine reaching the crown of the heads, the crownbeing the upper surface of the broccoli head covered by the florets. Thepresent commercial heading broccoli varieties all have a high canopythat shades at least portions of the head, particularly at the margin ofthe crown, resulting in yellowing around the outer extremities of theharvested broccoli heads, sometimes even causing extensive yellowing ofindividual florets at the center of the crown.

Broccoli is typically planted in the range of 30,000 to 40,000 plantsper hectare, though in North America it is common to plant broccoli at ahigher density, of 40,000 to as high 100,000 plants per hectare. Athigher densities, the broccoli plants will produce smaller heads. Incommon with other cole crops, broccoli can be established in the fieldby direct-seeding or by transplanting. Many factors, such as soil type,organic matter content and soil moisture interact to influencegermination and emergence. A more uniform, as well as earlier, broccolicrop can be grown from transplants raised in plugs or flats in agreenhouse. Such transplants can be planted in the field during lateApril, although the plants must be hardened off before being set out.

The edible portion of broccoli is the unopened flowering heads. Broccoliheads are susceptible to a number of defects that may relate to climaticor growth aberrations, though some appear to be cultivar related. Manydefects can be avoided by harvesting at the correct stage so that theheads do not become overmature. A post-mature crop will show advancedflower development, with yellowing of the heads. Over-mature plants alsocommonly developing fibrous stems.

Harvesting at the correct stage and proper handling afterwards are veryimportant with broccoli, as it is a perishable commodity. For thisreason, uniformity of maturity and concentrated harvesting have been themost highly desirable characteristics in broccoli varieties.

Harvested broccoli is often cooled with packed ice or a hydro-coolerimmediately after harvest. Broccoli that is cooled and maintained at 32°F. and 95 to 100 percent relative humidity can be stored for 10 to 14days. If broccoli is stored this long, however, it will begin to loseits dark green color and firmness, affecting its marketability.

Since harvesting is the single most expensive cultural operation, it isimperative that these costs be kept to a minimum. The present trend isto harvest only the main terminal heads, usually by hand. Certainmechanical harvest aids are used, but complete mechanical harvesting hasnot been adopted. Use of modern, more uniform hybrids has enabledgrowers to complete harvesting in two or, at the most, three manual cutsthrough the field.

In a study reviewing harvest practices from 1985-1990 in the UnitedStates, the time required for cutting broccoli was reported to be on theorder of 60 manhours/ha. Overall costs for cut/pack/haul/cool and sellwas reported as $2125/ha, with the cost of the cut alone being $500/ha.The labor requirements for harvesting are well over 50% of the totallabor costs for growing broccoli.

Converting from hand to machine harvesting of broccoli could reducethese labor requirements by a great deal. However, in testing differentcultivars, transplant times, growing techniques and harvest methods, arecent study determined that once over mechanical harvest of broccoliinflorescences, or heads, compared to the graduated traditionalhand-harvest (picking repeatedly 6 to 8 times), results in a yieldreduction on the order of 49% to 60%, depending on the variety. Acombination of hand harvest for the primary heads, followed by amechanical picking of the secondary heads was proposed as reducing yieldlosses, though still on the order of about 23% (Dellacecca, V. 1996, Newagrotechniques to promote broccoli picking. Acta Hort. (ISHS)407:347-352).

There have been efforts aimed at the improvement of broccoli to producevarieties better suited to mechanized harvesting. One factor limitingthe performance of a mechanical harvester is the phenotypic appearanceof the broccoli varieties and a lack of uniformity in maturity (Casada,J. H.; Walton, L. R.; Bader, M. J. (1988) Single pass harvesting ofbroccoli, Am Soc Agr Eng Microfiche Collect. (fiche #88-1041) p. 11;Bon, T. A. (1997) Senior design project development of a non-selectivebroccoli harvester, American Society of Agricultural Engineers No.97-1018, pp 17). Generally, there is wider acceptable maturity range forprocessing broccoli compared with fresh market broccoli, which requiresa more uniform product (Shearer, S. A.; Jones, P. T.; Casada, J. H.;Swetnam, L. D. (1991). A cut-off saw mechanism for selective harvest ofbroccoli. Transactions of the American Society of Agricultural Engineers34 (4): 16231628.)

Thus, the selection of appropriate broccoli plant types for uniformityof maturity has been identified as one factor in the success of anybroccoli harvester project (Bon, T. A., 1997). Harvesting of broccoli,either by hand or machine, could also be facilitated by an elongatedgrowth habit that results in the protrusion, or exsertion, of the headabove the general level of the broccoli foliage (Baggett, J. R., Kean,D., & Kasimor, K. (1995). Inheritance of internode length and itsrelation to head exsertion and head size in broccoli, J. Am. Society ofHort Sci. 120 (2): 292-296).

Another issue is that in harvesting broccoli leaves attached to thesevered head must be removed manually. Accomplishing this taskmechanically presents a further obstacle in the development of fullmechanisation of harvest. (Casada Shearer, S. A. and P. T. Jones (1991)Development of a mechanized selective harvester for cole crops, Am Socof Agr Engineers. Albuquerque, N. Mex., Jun. 23-26, 1991, Paper#91-1018, p 17). In this regard, incorporating mechanical defoliation ofthe broccoli plants into a harvester design is an area undergoinginvestigation, in the hope that successful implementation of adefoliation operation into a harvester would improve the overallefficiency of the harvest and packing (Bon, T. A., 1997).

The successful development of mechanized harvest would greatly improvethe overall efficiency of the harvest and packing (Bon, T. A., 1997).However, attempts to develop a broccoli harvester have not beensuccessful with present day broccoli plant types, due in part to themany simultaneous problems that must be overcome in adapting broccolivarieties for mechanization. In one article this problem is presented asrequiring the selection of varieties with their heads well above theground, with a more open leaf posture, and with leaves that are wellseparated from (or uncover) the bottom of the head. (Chou broccoli:Larecolte mecanique devient possible. A&D, 07/2001 #68. Also in UNILETinformations, #107-Janvier 2001). To date, the development of a broccoliplant type simultaneously providing these multiple solutions in acommercially acceptable context has presented an insurmountable problemfor the breeding community.

SUMMARY OF THE INVENTION

The present invention provides a broccoli plant adapted for ease ofharvest, with the traits of an exerted head having a crown, or top ofthe head of the broccoli, that is higher than the leaf canopy and aharvestable head of at least about 200 grams when planted at a densityof 40,000 plants per hectare, where the harvestable head comprises thetop 25 centimeters of the stalk.

The invention further provides broccoli heads produced by and harvestedfrom such broccoli plants.

In one preferred embodiment, the broccoli plants have a leafless traitalong the stalk, such that within 25 centimeters of the crown the plantproduces substantially no leaves or petioles having a surface areagreater than about 30 square centimeters, more preferably no greaterthan about 20 square centimeters.

In a further improved embodiment, the broccoli plant producessubstantially no leaves or petioles within 25 centimeters of the crownhaving a surface area of greater than about 10 square centimeters, mostpreferred being such a plant producing substantially no leaves orpetioles within 25 centimeters of the crown.

In another preferred embodiment, the crown of the broccoli plant will beexerted at least about 10 centimeters higher than the topmost leaf ofthe canopy, more preferably at least about 15 centimeters higher thanthe topmost leaf of the canopy, and most preferred at least about 25centimeters higher than the topmost leaf of the canopy.

In one preferred embodiment, the broccoli plant produces a harvestablehead of at least about 250 grams, more preferably at least about 350grams.

In a different preferred embodiment the broccoli plant produces aharvestable head of at least about 120 grams when planted at a densityof 80,000 plants per hectare, more preferably at least about 150 grams,and most preferably at least about 200 grams when grown at that density.

The invention also provides a plurality of such broccoli plants grown ina field of broccoli. In a preferred embodiment, substantially all of theplants mature at the same time, and more preferably all of the matureplants grow to substantially the same height.

The present invention also provides a new method of producing a broccolicrop comprising the step of growing a plurality of broccoli plants andharvesting the heads of the broccoli plants by mechanical means, wherebythe plants are characterized in having an exerted head having a crownhigher than the leaf canopy and a harvestable head of at least about 200grams when planted at a density of 40,000 plants per hectare, whereinthe harvestable head comprises the top 25 centimeters of the stalk, andwherein the mechanical means comprises means for severing the heads andmeans for collecting severed heads.

In one preferred embodiment, the broccoli plant produces a uniformlygreen head having substantially no yellowing about the margin of theflorets, on the order of about 10% or less of any floret surface showinga change from uniform green to yellow.

In a preferred embodiment of the method of the invention, the mechanicalmeans further comprises means for grasping the heads and guiding theheads to the severing means, more preferably the severing means guidedthrough the plurality of broccoli plants at a substantially constantheight above the soil.

In a further preferred embodiment, there is provided means, andcollecting means, for advancing the severing means through the pluralityof broccoli plants, which are more preferably provided in a combination.

The invention also provides seed of inbred broccoli line designated932779, a sample of such seed having been deposited as NCIMB 41218Brassica oleracea var botrytis 932779, having a deposit date of 28 Apr.2004, seed of an inbred broccoli plant designated 970249, a sample ofsuch seed having been deposited NCIMB 41219 Brassica oleracea varbotrytis 970249, having a deposit date of 28 Apr. 2004, and seed of aninbred broccoli plant designated 970195, a sample of such seed havingbeen deposited as NCIMB 41216 Brassica oleracea var botrytis 970195,having a deposit date of 28 Apr. 2004.

The invention further provides hybrid broccoli seed having as one parenta plant grown from such seed, as well as a broccoli plant, or partsthereof, produced by the hybrid seed. The invention thus provides seedof a hybrid broccoli plant designated SVR 4, a sample of such seedhaving been deposited as NCIMB 41214 Brassica oleracea var botrytis SVR4, having a deposit date of 28 Apr. 2004, seed of an inbred broccoliplant designated SVR 1, a sample of such seed having been depositedNCIMB 41215 Brassica oleracea var botrytis SVR 1, having a deposit dateof 28 Apr. 2004, and seed of an inbred broccoli plant designated SVR 5,a sample of such seed having been deposited as NCIMB 41217 Brassicaoleracea var botrytis SVR 5, having a deposit date of 28 Apr. 2004.

In a preferred such embodiment, the invention provides a plurality ofsuch broccoli plants in a field of planted broccoli, as well as broccoliheads harvested from such a field

The invention further includes such broccoli plants, or parts thereof,transformed to contain one or more transgenes operably linked toregulatory elements functional in a broccoli plant.

The invention also includes pollen, ovules or tissue culture derivedfrom cells of broccoli seed or plants of the invention, where the tissueculture comprises cells or protoplasts from a tissue from cells fromleaves, pollen, embryos, roots, root tips, anthers, flowers, fruit, andseeds, as well as a broccoli plant regenerated from such tissue culture.

The patent or application file contains at least one drawing executed incolor. Copies of this patent or patent application publication withcolor drawing(s) will be provided by the Office upon request and paymentof the necessary fee.

BRIEF DESCRIPTION OF THE DRAWINGS

The patent or application file contains at least one drawing executed incolor. Copies of this patent or patent application publication withcolor drawing(s) will be provided by the Office upon request and paymentof the necessary fee.

Various exemplary embodiments of this invention will be described indetail, with reference to the following figures, wherein:

FIG. 1 of the accompanying drawings is a picture showing the typicalgrowth habit of a conventional broccoli line, General, of Seminis Seeds.

FIG. 2 of the accompanying drawings is a picture showing the growthhabit of the hybrid line SVR1.

FIG. 3 of the accompanying drawings is a pedigree showing thedevelopment of the broccoli plant of the invention designated 970195.

FIG. 4 of the accompanying photographic drawings illustrates a pictureof the inbred broccoli plant designated 970192.

FIG. 5 of the accompanying photographic drawings illustrates a pictureof the inbred broccoli plant designated PLH42.

FIG. 6 of the accompanying photographic drawing illustrates a picture ofthe hybrid broccoli plant designated SVR 1.

FIG. 7 of the accompanying photographic drawing illustrates a picture ofthe hybrid broccoli plant designated SVR 4 growing in a field.

FIG. 8 of the accompanying photographic drawing illustrates a picture ofthe hybrid broccoli plants designated SVR 5 growing in a field.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Technical or scientific terms used herein shall have the ordinarymeaning accepted by those of skill in the art, unless defineddifferently herein. Descriptions of botanical terms can be found innumerous texts on the subject. See, for instance; Hickey, M., and King,C., (2001). Cambridge Illustrated Glossary of Botanical Terms,Cambridge, UK: Cambridge University Press.

Referring now to FIG. 1, there is shown a conventional broccoli plant ofthe line General (Seminis Seeds). FIG. 2 shows a broccoli plant made inaccordance with the present invention, the hybrid plant SVR1. The plantsin FIG. 1 and FIG. 2 were grown in a field trial under similarconditions. In FIGS. 1 and 2 the leaves facing the camera have been cutaway to better reveal the growth habit of the respective plants. Thecomponents of a harvested broccoli head comprises the floret clusters,the tops of which form an upper, deep green and generally convexsurface, also referred to herein as the crown. Commonly, a region of thestalk supporting the floret clusters is harvested with the broccoli, andforms a part of the edible broccoli head.

The invention provides an inbred line, adapted to 100% mechanicalharvest, that combines high head exsertion with a lack of leafdevelopment on the stalk below the head (FIG. 2). Some prior varieties,such as Caravel and Corvet, have shown a relatively raised head butstill have large leaves prevalent on the stem directly below the head.There are also purple sprouting varieties with bushy elevated heads,again, that have many leaves on the stem below the head.

The type of broccoli described herein makes it possible to mechanicallyharvest a field of broccoli, with the trait of a broccoli plant havinghead exsertion above the plant canopy combined with a substantialabsence of leaves and leaflets along the stalk immediately below thehead. The variety also produces broccoli plants showing uniformity forboth maturity and height, and that will produce commercially acceptableheads.

With the present invention a harvester especially adapted for harvestingthe high head exsertion types is also provided, with cutting meansprovided for severing the heads at a point along the stalks and abovethe canopy, and means for collecting and conveying the severed heads.

Conventional broccoli typically has large leaves and petioles growingout of the stem up to and just below the head. The improved variety hasonly a few very small leaves at the same positions below the head.

The development of commercial broccoli hybrids involves the developmentof homozygous inbred parental lines through techniques well known to theart. Generally, two or more germplasm sources or gene pools are combinedto develop superior breeding lines. Desirable inbred or parent lines aredeveloped by continuous selection, followed up with several generationsof selfing until the lines are sufficiently uniform. Alternatively,anther or microspore culture (DH lines) may be used followed byselection of the best breeding lines and testing progeny in varioushybrid combinations.

Once the inbred lines that give the best hybrid performance have beenidentified, hybrid seed can be produced indefinitely, as long as thehomogeneity and the homozygosity of the inbred parents is maintained.The term inbred broccoli plant also includes any single gene conversionsof that inbred. The term single gene converted plant as used hereinrefers to those broccoli plants which are developed by a plant breedingtechnique called backcrossing wherein essentially all of the desiredmorphological and physiological characteristics of an inbred arerecovered in addition to the single gene transferred from the donorparent into the inbred via the backcrossing technique.

For large scale hybrid seed production, different systems of crosspollination, based on self-incompatibility, or, alternatively,cytoplasmic male sterility (CMS), are used. These techniques are wellknown in the art. Large scale increase of the hybrid parents (inbredlines) is done by self-pollination, where necessary facilitated byincreasing the concentration of CO₂ to overcome theself-incompatibility, or bud pollination using hand labor. Such largescale increase of inbred lines is most commonly done in a greenhouse orplastic house. This practice of parent line seed production leads togood quality seed and disease control. Inbred plants include broccolitypes 970192, 932779, 970249, PLH42 and 970195. FIG. 3 provides apedigree chart following the selections made in the development of970195.

The commercial hybrid seed is produced in the open field byinter-planting rows of the seed parent and the pollinator parent, whereself-incompatibility or CMS of the seed parent prevents self pollinationand ensures the harvesting of hybrid F1 seed, in methods well known inthe art.

For broccoli hybrid seed production, the most modern system is using CMSthat was introgressed into Brassica oleracea from radish. For broccolihybrid seed production, the modern system uses CMS that was introgressedinto Brassica oleracea from radish (Ogura, H. (1968). Studies on the newmale sterility in Japanese radish, with special reference to theutilization of this sterility towards practical raising of hybrid seed.Mem Fac Agric Kagoshima Univ. 6:39-78).

The head exsertion broccoli parent line has shown uniformity andstability for all traits. The parent lines have been maintained bybud-pollination (in case of self-incompatibility of the hybrid parentsof the three homozygous lines deposited), or in case of CMS seed parentspollinated by its maintainer, and planted for a sufficient number ofgenerations, with careful attention to uniformity of plant type, toensure homozygosity and phenotypic stability. No variant traits havebeen observed or are expected.

The exerted broccoli type brings the head far above the canopy. Thebroccoli further has no large leaves in the area of the stalk that isimmediately below the head, and so it can be harvested at the level ofthe stem in a manner that is free of interference of the leaves,including petioles, which not only eases manual harvest but makespossible the efficient once-over mechanical harvesting of the crop, inboth cases saving labor costs. Conventional broccoli can only beharvested manually, making it both time consuming and costly as theproduct sits deep in the crop and the leaves must further be manuallystripped from the stem.

The broccoli provides uniformity in other traits that will maximizeyield in once-over harvest, including the timing of maturation andgrowth characteristics of the broccoli on the plant, as well as headexsertion (raised head) trait. The whole head and/or florets of thebroccoli inbred line designated 970192 (plh26/plh33), shown in FIG. 4,demonstrate these traits.

A further advantage of the new varieties is the uniformity of color,i.e., that the broccoli plants produce heads that stick out of thecanopy and are exposed to sunlight to a higher and more consistentdegree than for conventional broccoli plants, resulting in a uniformlydeep green color for the product, with substantially no yellowing aboutthe margin of the crown. The reduced canopy means that light can betterreach all sides of the heads, as well as individual florets, becomeuniformly green after floretting, instead of being green with yellowedges as is the case with conventional broccoli being shaded along theedges by the leaf canopy. This is a very desirable characteristic forbroccoli processors.

By substantially no yellowing, it is meant that the harvested heads,even when viewed from the side, show a uniform deep green color, withvery little or no lightening or yellowing a the edges of the crown as awhole. This is also true for individual florets, which have greatlyreduced yellowing about the floret margins. It has been observed thatfor the broccoli heads produced by the plants having the exerted headtrait, that less than about 10% of any floret will show a change from auniform green to yellow at the margins.

The present invention also contemplates a broccoli plant regeneratedfrom a tissue culture of an inbred or hybrid plant of the presentinvention. Methods are well known in the art for tissue cultureregeneration of broccoli, and further that such methods can be used forthe in vitro regeneration of broccoli or transformed broccoli (see,e.g., U.S. Pat. No. 5,188,958, Moloney, et al., Feb. 23, 1993).

The development of the head exsertion broccoli type began as an effortto develop broccoli plants for easier hand or mechanical harvest incombination with good horticultural adaptation. For hand or machineharvesting an elongated growth habit of the main stem bearing thebroccoli head and protrusion above the leaf canopy was the goal. Thischaracter is defined as head exsertion.

Other characteristics thought to be important for ease of harvestingwere head height, along with short leaf petioles, facilitating theexsertion of the head above the canopy. Another character selected forwas uniformity of head height.

The following examples are intended to illustrate but not to limit theinvention.

Example 1 Development of Germplasm

Both proprietary and available public research lines were availablehaving a raised head (RH) trait. For instance, the Oregon StateUniversity (OSU) broccoli breeding program had lines with a moderateraised head, and several accessions were obtained from the OSU breedingprogram. These lines were designated as OSU-102 and OSU-111. Theseaccessions produced poor head size, poor head quality, generally, andleaves on the stem just below the head which rendered such linesunsuitable as parents for commercially viable hybrids. Selection forbetter raised head traits and higher internode lengths consistently ledto lower head weights. (Baggett, et al., 1995). The present inventionhas found a solution to this problem, as further described herein.

Proprietary accessions selected at the start of the breeding projectwere designated DH-MRE-7, DH MRD1-1, GM1-6, B19, DH E-47, EC-2, SH2,EC-2, SH-2, DH M-84, HCH, GB-7, HBH-6 and DH GV-37. All of these lineswere elite parent lines developed in the Seminis breeding program, thatwere used for the production of commercial hybrids as long ago as the1970s. These lines were chosen at least partly to compensate for thedefects observed of the horticultural characteristics of the OSU lines.

More specifically, the proprietary lines had very good general combiningability, resistance to disease, particularly to downy mildew(Peronospora parasitica), already showed reasonably good RH traits,short leaves about the head, good head height and head-heightuniformity, as well as resistance to bacterial soft rot (Erwinia andPseudomonas bacteria). The main characteristics of each of these linesare summarized in Table 1, below.

TABLE 1 Accession or line number Description OSU-102 Compare withOSU111, little more vigor OSU-111 Small plant, average RH, leaves onstem, large bead DH-MRE-7 Downey Mildew resistant, good bead DH MRD1-1Downey Mildew resistant, good bead GM1-6 Relatively good raised head,fine bead, good combining ability, used in many commercial Seminishybrids (Corvet, Cruiser etc), leaves on stem below the head. B19Earliness, combining ability, used in commercial Seminis hybrids. DHE-47 Brings in head weight and color EC-2 Relatively RH, large bead DHGV-37 Firmness and bead quality SH-2 Combining ability, geneticdistance, color, vigor, wetrot tolerance HBH-6 Earliness DH M-84 Smallbead, quality of head, firmness HCH Compare HBH6 GB-7 Firmness and beadqualityThe designation DH designates double haploid, and indicates that thisline has been developed through either anther culture or microsporeculture, followed by chromosome doubling.

In general, the better RH lines had little (OSU) or average (GM1.6, EC2)head quality. In the better quality lines, i.e., having good firmness,bead size, color, Downey Mildew resistance, etc., the RH trait wasgenerally missing. There were no lines available that combined the RHtrait with suitable quality, and none that added the trait ofsubstantially no leaves present below the head to give an exsertedappearance.

The lines have been continuously crossed and selected in variouscombinations since the 1980s. Progeny plants (F1) of each cross wereselected for their phenotypic appearance for head exsertion incombination with favorable horticultural characteristics for all otherimportant horticultural traits of head traits. The selected plants fromthe best families were crossed again with other selected plants fromother families. Occasionally, between two crossing cycles selectedplants were selfed for one or two generations (F2, F3) to obtain betteruniformity of the lines.

The best plants of these lines were crossed again. This breedingprocedure is known as the modified family selection, as is described instandard text books of plant breeding, i.e., Allard, R. W., Principlesof Plant Breeding (1960) New York, N.Y., Wiley, pp 485; Simmonds, N. W.,Principles of Crop Improvement (1979), London, UK, Longman, pp 408;Sneep, J. et al., (1979) Tomato Breeding (p. 135-171) in: Breeding ofVegetable Crops, Mark J. Basset, (1986, editor), The Tomato crop: ascientific basis for improvement, by Atherton, J. G. & J. Rudich(editors), Plant Breeding Perspectives (1986); Fehr, Principles ofCultivar Development-Theory and Technique (1987) New York, N.Y.,MacMillan.

In the course of the selection program several lines showing favorablecharacteristics were selected which were designated as PLH, andassociated with a sequence number. Surprisingly, there is little or nodiscernible loss in yield in the raised head type of broccoli. This issomewhat surprising given the amount of additional stalk required toattain exsertion of a heavy head from the foliage.

Only after a succession of years of crossing and selection incombination with one or two generations of selfing was it shown that thegenetic linkage that existed between head exsertion and poorhorticultural and head quality characteristics could be broken. Theprogress in any generation was always small and difficult to quantifyfrom generation to generation.

The best lines now available include 970195 (based on selection from thecross PLH 2546 and PLH 33), 970192 (selected from the cross PLH 26 withPLH 33), 970249 (selected from a cross between DH M 84 and MRD 6),932779 (selected from a cross between PLH 10 and DC3EC6), and PLH 42(selected from a cross between DC3EC6 and PLH 10). Seed of lines 932779,970249, and 970195 are the subject of a NCIMB deposit. PLH 10 was itselfa selection from a cross of HBH 6 and OSU-111.

A pedigree showing the development of the line 970195 is summarized inFIG. 3, demonstrating a typical series of crosses and selections used indevelopment of the varieties.

The whole head and/or florets of the broccoli inbred line 970192(plh26/plh33), FIG. 4, demonstrates the head exsertion trait in aninbred line. The head exsertion of this broccoli line has shownuniformity and stability for all traits over several years. It has beendeveloped and maintained by bud pollination for five generations withcareful attention to uniformity of plant type to ensure homozygosity andphenotypic stability. No variant traits have been observed or areexpected.

Inbred lines 970195 and 970249 have similar raised head traits.Development and maintenance of these lines was analogous to that forline 970195.

PLH 42 (FIG. 5), shows good head exsertion in accordance with theinvention, with few, small leaves present on the stalk below the head.It has been developed and maintained by bud pollination for sixgenerations with careful attention to uniformity of plant type to ensurehomozygosity and phenotypic stability. No variant traits have beenobserved or are expected.

932779 has a similar background to PLH42. It is an early maturing linethat shows good head exsertion and a good quality head with nice beadand firmness, with a number of smaller leaves on the stalk below thehead. The Downey mildew resistance is very high and the color of thehead dark green.

Example 2 Production of Exserted Head Broccoli Hybrid

The favored inbred lines have been used to produce hybrid combinations.SVR 1 was produced by crossing PLH42×DH PLH13 (FIG. 6). It has thetraits of extreme RH, extreme early, extreme dark color, fine bead, goodheat tolerance, good wetrot tolerance, good uniformity, Downey MildewResistance, DMR, fine stem, some leaves below the head, head weight250-300 gr/head at 40.000 pl/ha, good adaptability to climate andseasons. The leaves below the head are very few, having a very smallsquare area.

SVR 4 was produced by crossing PLH26/PLH33×NjaECB (FIG. 7). It showsgood RH, medium maturity, semi crown, relatively large bead, head weight300350 gr/head at 40.000 pl/ha, with a cleaner stem than SVR1.

SVR 5 was produced by crossing PLH2546/PLH33×NjaECB. Its maturity islike SVR4, deeply branched head, medium raised head, also a cleaner stemthan SVR1, head weight 350-400 gr/head at 40.000 pl/ha, extremely greenfloret color, all green floret, more of a processing/floretting type,with a deeply branched head (FIG. 8).

Example 3 Harvesting of Exserted Head Broccoli

A field of broccoli plants is grown to maturity, and the heads harvestedby mechanical means of grasping the heads, severing the heads andcollecting the severed heads on a conveyor. It is found that the greatmajority of broccoli heads can be harvested in this manner from a fieldof broccoli plants, saving time and expense of hand harvesting. Theexserted head trait with little or no foliage below the head allows therunning of a mechanized harvest without damage to the broccoli heads orfouling of the harvester.

Deposit Information

A deposit of the Seminis Vegetable Seeds proprietary inbred and hybridbroccoli lines disclosed above and recited in the appended claims havebeen made with NCIMB Ltd, 23 St. Machar Drive, Aberdeen AB24 3RY. Thedate of each of these deposits was 28 Apr. 2004. The deposit of 2500seeds for each variety were taken from the same deposit maintained bySeminis Vegetable Seeds since prior to the filing date of thisapplication. Upon issuance of a patent, all restrictions upon thedeposit will be removed, and the deposit is intended to meet all of therequirements of 37 C.F.R. §1.801-1.809. The NCIMB accession numbers forinbred lines 932779, 970249, and 970195 are, respectively, NCIMB 41218Brassica oleracea var botrytis 932779, NCIMB 41219 Brassica oleracea varbotrytis 970249, and NCIMB 41216 Brassica oleracea var botrytis 970195.Hybrid broccoli seed SVR 4, SVR 1 and SVR 5 have NCIMB accession number,respectively, NCIMB 41214 Brassica oleracea var botrytis SVR 4, NCIMB41215 Brassica oleracea var botrytis SVR 1, and NCIMB 41217 Brassicaoleracea var botrytis SVR 5. These deposits will be maintained in thedepository for a period of 30 years, or 5 years after the last request,or for the effective life of the patent, whichever is longer, and willbe replaced as necessary during that period.

The patent or application file contains at least one color drawingexecuted in color. Copies of this patent or patent applicationpublication with color drawing(s) will be provided by the Office uponrequest and payment of the necessary fee.

Although the foregoing invention has been described in some detail byway of illustration and example for purposes of clarity andunderstanding, it will be obvious that certain changes and modificationsmay be practiced within the scope of the invention, as limited only bythe scope of the appended claims.

1.-63. (canceled)
 64. A broccoli plant comprising a harvestable headweight of at least about 200 grams when planted at a density of 40,000plants per hectare, wherein said plant produces no leaves or petioleseach having a surface area greater than about 30 square centimeterswithin 25 centimeters of the crown.
 65. The broccoli plant according toclaim 64, wherein said no leaves or petioles have a surface area greaterthan about 20 square centimeters.
 66. The broccoli plant according toclaim 64, wherein said no leaves or petioles have a surface area greaterthan about 10 square centimeters.
 67. The broccoli plant according toclaim 64, wherein said broccoli plant produces no leaves or petioleswithin 25 centimeters of the crown.
 68. The broccoli plant according toclaim 64, wherein said broccoli plant produces a harvestable head of atleast about 120 grams when planted at a density of 80,000 plants perhectare.
 69. The broccoli plant according to claim 64, wherein saidbroccoli plant is cytoplasmically male sterile.
 70. The broccoli plantaccording to claim 64, wherein said broccoli plant produces aharvestable head of at least about 250 grams when planted at a densityof 40,000 plants per hectare.
 71. The broccoli plant according to claim64, wherein said broccoli plant produces a harvestable head of at leastabout 350 grams when planted at a density of 40,000 plants per hectare.72. The broccoli plant according to claim 64, wherein said broccoliplant produces a harvestable head of at least about 150 grams whenplanted at a density of 80,000 plants per hectare.
 73. The broccoliplant according to claim 64, wherein said broccoli plant produces aharvestable head of at least about 200 grams when planted at a densityof 80,000 plants per hectare.
 74. The broccoli plant according to claim64, wherein said broccoli plant produces a uniformly green head havingsubstantially no yellowing about the margin of the crown.
 75. Thebroccoli plant according to claim 64, obtainable by crossing a broccoliplant selected from the group consisting of: the inbred broccoli plantvariety designated 932779, a representative sample of said variety932779 having been deposited with the NCIMB under NCIMB Accession No.41218, the inbred broccoli plant variety designated 970249, arepresentative sample of said variety 970249 having been deposited withthe NCIMB under NCIMB Accession No. 41219, the inbred broccoli plantvariety designated 970195, a representative sample of said variety970195 having been deposited with the NCIMB under NCIMB Accession No.41216, the hybrid broccoli plant variety designated SVR 4, arepresentative sample of said variety SVR 4 having been deposited withthe NCIMB under NCIMB Accession No. 41214, the hybrid broccoli plantvariety designated SVR 1, a representative sample of said variety SVR 1having been deposited with the NCIMB under NCIMB Accession No. 41215,and the hybrid broccoli plant variety designated SVR 5, a representativesample of said variety SVR 5 having been deposited with the NCIMB underNCIMB Accession No.
 41217. 76. The broccoli plant according to claim 64,wherein said plant variety is an inbred or a hybrid.
 77. A plurality ofbroccoli plants according to claim 64 grown in a field of broccoli. 78.The plurality of broccoli plants according to claim 77, whereinsubstantially all of said plants mature at the same time.
 79. Theplurality of broccoli plants according to claim 77, wherein said matureplants grow to substantially the same height.
 80. A part of a broccoliplant obtainable from a plant according to claim
 64. 81. The part of abroccoli plant according to claim 80, wherein said part is a seed. 82.The part of a broccoli plant according to claim 80, wherein said part ispollen or an ovule.
 83. The part of a broccoli plant according to claim80, wherein said part is a severed broccoli head obtained by cutting theleafless stem at a predetermined position below the head.
 84. A progenyof a broccoli plant according to claim 64, wherein said progenycomprises a harvestable head weight of at least about 200 grams whenplanted at a density of 40,000 plants per hectare, wherein said plantproduces no leaves or petioles each having a surface area greater thanabout 30 square centimeters within 25 centimeters of the crown.
 85. Aprogeny of a broccoli plant according to claim 64, wherein said progenyis selected from the group consisting of: the inbred broccoli plantvariety designated 932779, a representative sample of said variety932779 having been deposited with the NCIMB under NCIMB Accession No.41218, the inbred broccoli plant variety designated 970249, arepresentative sample of said variety 970249 having been deposited withthe NCIMB under NCIMB Accession No. 41219, the inbred broccoli plantvariety designated 970195, a representative sample of said variety970195 having been deposited with the NCIMB under NCIMB Accession No.41216, the hybrid broccoli plant variety designated SVR 4, arepresentative sample of said variety SVR 4 having been deposited withthe NCIMB under NCIMB Accession No. 41214, the hybrid broccoli plantvariety designated SVR 1, a representative sample of said variety SVR 1having been deposited with the NCIMB under NCIMB Accession No. 41215,and the hybrid broccoli plant variety designated SVR 5, a representativesample of said variety SVR 5 having been deposited with the NCIMB underNCIMB Accession No.
 41217. 86. A broccoli plant produced by growing aseed according to claim 81, wherein said broccoli plant produced bygrowing said seed comprises a harvestable head weight of at least about200 grams when planted at a density of 40,000 plants per hectare,wherein said plant produces no leaves or petioles each having a surfacearea greater than about 30 square centimeters within 25 centimeters ofthe crown.
 87. A method of producing a crop of broccoli heads comprisinggrowing a plurality of broccoli plants according to claim 77 andharvesting the heads of said broccoli plants by 100% mechanical means,wherein said mechanical means comprises means for severing said heads.88. The method of claim 87, wherein said severing means is guidedthrough said plurality of broccoli plants at a constant height above thesoil.
 89. The method according to claim 87, wherein said mechanicalmeans is a harvest machine comprising a blade at a predeterminedposition above the soil and comprising means for collecting the severedbroccoli heads.
 90. A method of producing a broccoli crop comprisinggrowing a plurality of broccoli plants according to claim 77 andharvesting the heads of said broccoli plants by 100% mechanical means.91. A crop of severed broccoli heads obtainable by the method accordingto claim 87, wherein the stalks of said heads are leafless and have apredetermined length and said heads are uniformly green.
 92. A broccolitissue culture produced from cells of the broccoli plant according toclaim
 64. 93. The tissue culture according to claim 92, comprising cellsor protoplasts from a tissue selected from the group consisting ofleaves, pollen, embryos, roots, root tips, anthers, flowers, fruit, andseeds.
 94. A broccoli plant regenerated from the tissue culture of claim92 comprising a harvestable head of at least about 200 grams whenplanted at a density of 40,000 plants per hectare, wherein said broccoliplant produces no leaves or petioles each having a surface area greaterthan about 30 square centimeters within 25 centimeters of the crown.